diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index a8260370..d3036a46 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -5,22 +5,64 @@ name: CI
 on: [ push, pull_request, workflow_dispatch ]
 jobs:
   test:
+    # https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#choosing-github-hosted-runners
     runs-on: ubuntu-latest
-    timeout-minutes: 10
-    strategy:
-      matrix:
-        # TODO: need add back java 8 later
-        # java: [ 8, 11, 17, 19 ]
-        java: [ 17, 19 ]
-      fail-fast: false
-      max-parallel: 64
-    name: Test JDK ${{ matrix.java }}
+    timeout-minutes: 20
+    name: test by multiply java versions
 
     steps:
       - uses: actions/checkout@v3
-      - uses: actions/setup-java@v3
+
+      - name: setup java19
+        uses: actions/setup-java@v3
+        with:
+          java-version: 19
+          distribution: temurin
+          cache: maven
+
+      - name: build and test with java 19
+        run: >
+          ./mvnw -V --no-transfer-progress
+          help:evaluate -Dexpression=settings.localRepository
+          -DperformRelease -P'!gen-sign'
+          clean install
+
+      - name: setup java8
+        uses: actions/setup-java@v3
         with:
-          java-version: ${{ matrix.java }}
+          java-version: 8
           distribution: zulu
           cache: maven
-      - run: ./mvnw -V --no-transfer-progress clean package
+
+      - run: ./mvnw -V surefire:test
+
+      - name: setup java11
+        uses: actions/setup-java@v3
+        with:
+          java-version: 11
+          distribution: microsoft
+          cache: maven
+
+      - run: ./mvnw -V surefire:test
+
+      - name: setup java17
+        uses: actions/setup-java@v3
+        with:
+          java-version: 17
+          distribution: microsoft
+          cache: maven
+
+      - run: ./mvnw -V surefire:test
+
+      - name: setup java20
+        uses: actions/setup-java@v3
+        with:
+          java-version: 20-ea
+          distribution: zulu
+          cache: maven
+
+      - run: ./mvnw -V surefire:test
+
+      - name: remove self maven install files
+        run: rm -rf $HOME/.m2/repository/io/foldright/cffu/
+
diff --git a/pom.xml b/pom.xml
index fe37e477..d930e820 100644
--- a/pom.xml
+++ b/pom.xml
@@ -29,8 +29,7 @@
 	</issueManagement>
 
 	<properties>
-		<!-- TODO: set back to 1.8 after CI setting -->
-		<maven.compiler.source>17</maven.compiler.source>
+		<maven.compiler.source>1.8</maven.compiler.source>
 		<maven.compiler.target>${maven.compiler.source}</maven.compiler.target>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<maven.deploy.skip>false</maven.deploy.skip>
@@ -518,7 +517,6 @@
 									Maven javadoc Search redirects to "/undefined/.." url - Stack Overflow
 									https://stackoverflow.com/questions/52326318
 								-->
-								<additionalOption>--no-module-directories</additionalOption>
 								<additionalOption>-html5</additionalOption>
 							</additionalOptions>
 							<additionalJOptions>
@@ -672,7 +670,7 @@
 			</build>
 		</profile>
 		<profile>
-			<id>force-jdk11-when-release</id>
+			<id>force-jdk-version-when-release</id>
 			<activation>
 				<property>
 					<name>performRelease</name>
@@ -696,7 +694,7 @@
 								<configuration>
 									<rules>
 										<requireJavaVersion>
-											<version>11</version>
+											<version>19</version>
 										</requireJavaVersion>
 									</rules>
 								</configuration>
diff --git a/src/test/java/io/foldright/cffu/CffuTest.java b/src/test/java/io/foldright/cffu/CffuTest.java
index 702c08dc..362343c9 100644
--- a/src/test/java/io/foldright/cffu/CffuTest.java
+++ b/src/test/java/io/foldright/cffu/CffuTest.java
@@ -65,7 +65,7 @@ void test_resultAllOf_exceptionally() throws Exception {
         try {
             Cffu.resultAllOf(
                     CompletableFuture.completedFuture(n),
-                    CompletableFuture.failedFuture(rte),
+                    failedCf(),
                     CompletableFuture.completedFuture(s)
             ).get();
 
@@ -80,7 +80,7 @@ void test_resultOf_2_or_3_exceptionally() throws Exception {
         try {
             Cffu.resultOf(
                     CompletableFuture.completedFuture(n),
-                    CompletableFuture.failedFuture(rte)
+                    failedCf()
             ).get();
 
             fail();
@@ -91,7 +91,7 @@ void test_resultOf_2_or_3_exceptionally() throws Exception {
         try {
             Cffu.resultOf(
                     CompletableFuture.completedFuture(n),
-                    CompletableFuture.failedFuture(rte),
+                    failedCf(),
                     CompletableFuture.completedFuture(s)
             ).get();
 
@@ -124,7 +124,7 @@ public void test_anyOf_exceptionally() throws Exception {
             Cffu.anyOf(
                     createNormallyCompletedFutureWithSleep(another_n),
                     createNormallyCompletedFutureWithSleep(another_n),
-                    CompletableFuture.failedFuture(rte)
+                    failedCf()
             ).get();
 
             fail();
@@ -135,7 +135,7 @@ public void test_anyOf_exceptionally() throws Exception {
         try {
             Cffu.anyOf(Arrays.asList(
                     createNormallyCompletedFutureWithSleep(another_n),
-                    CompletableFuture.failedFuture(rte),
+                    failedCf(),
                     createNormallyCompletedFutureWithSleep(another_n)
             )).get();
 
@@ -159,4 +159,11 @@ public void test_anyOf_exceptionally() throws Exception {
                 createExceptionallyCompletedFutureWithSleep(rte)
         )).get());
     }
+
+
+    private static <T> CompletableFuture<T> failedCf() {
+        CompletableFuture<T> cf = new CompletableFuture<>();
+        cf.completeExceptionally(rte);
+        return cf;
+    }
 }
diff --git a/src/test/java/io/foldright/showcases/CompletableFutureUsageShowcaseTest.kt b/src/test/java/io/foldright/showcases/CompletableFutureUsageShowcaseTest.kt
index 8fd9321a..fa25ca80 100644
--- a/src/test/java/io/foldright/showcases/CompletableFutureUsageShowcaseTest.kt
+++ b/src/test/java/io/foldright/showcases/CompletableFutureUsageShowcaseTest.kt
@@ -330,7 +330,7 @@ class CompletableFutureUsageShowcaseTest : FunSpec({
         sequenceChecker.assertSeq("in completeAsync", 4)
     }
 
-    test("timeout control: normally completed with replacement value") {
+    test("timeout control: normally completed with replacement value").config(enabledIf = java9Plus) {
         val f = CompletableFuture.supplyAsync {
             sleep(10)
             n
@@ -340,7 +340,7 @@ class CompletableFutureUsageShowcaseTest : FunSpec({
         f.get() shouldBe anotherN
     }
 
-    test("timeout control: exceptionally completed with java.util.concurrent.TimeoutException") {
+    test("timeout control: exceptionally completed with java.util.concurrent.TimeoutException").config(enabledIf = java9Plus) {
         val f = CompletableFuture
             .supplyAsync {
                 sleep(10)
@@ -356,9 +356,9 @@ class CompletableFutureUsageShowcaseTest : FunSpec({
         f.get() shouldBe anotherN
     }
 
-    test("delay execution") {
+    test("delay execution").config(enabledIf = java9Plus) {
         val tick = currentTimeMillis()
-        val delay = 5L
+        val delay = 10L
 
         val delayer = CompletableFuture.delayedExecutor(delay, TimeUnit.MILLISECONDS)
 
@@ -367,7 +367,7 @@ class CompletableFutureUsageShowcaseTest : FunSpec({
             currentTimeMillis() - tick
         }, delayer).get()
 
-        duration.shouldBeBetween(delay, delay + 2)
+        duration.shouldBeBetween(delay, delay + 4)
     }
 
     xtest("performance CF then*").config(invocations = 10) {